After the chairman of the tournament’s South African organizing committee had said he would consider a ban on the monotone trumpets, Blatter axed the idea of a ban in comments posted to the short-form web site.

“I don’t see banning the music traditions of fans in their own country. Would you want to see a ban on the fan traditions in your country?” Blatter wrote.

“I have always said that Africa has a different rhythm, a different sound.”

Asked by the BBC if a ban was an option, Jordaan said: “If there are grounds to do so, yes.”

“We have asked for no vuvuzelas during national anthems or during stadium announcements. I know it’s a difficult question,” he added. “We’re trying to manage the best we can.”

Jordaan’s comments came after complaints from players and broadcasters who said their commentators are struggling to make themselves heard above the noise, which has been compared to a hornets’ nest.

Portugal’s Cristiano Ronaldo was the latest World Cup star to voice unease about the trumpet, telling reporters that it affected players’ focus.

“It is difficult for anyone on the pitch to concentrate,” the Real Madrid star told reporters. “A lot of players don’t like them, but they are going to have to get used to them.”

A recent survey found the sound emitted by a vuvuzela could reach 127 decibels — louder than a drum’s 122 decibels, or a referee’s whistle at 121.8 decibels.

But hitting such ear-piercing noise levels takes some practice.

A group of fans at Japan’s World Cup opener against Cameroon on Monday was having trouble getting any noise out of the instrument.

“Last night we bought some vuvuzela but it is hard to blow them,” said Mitsutaka Kurata.

A group of security guards at Bloemfontein’s Free State Stadium was teaching the Japanese fans how to blow the controversial instruments.

Vuvuzelas are modern spin-offs of traditional instruments made from spiralling kudu horns. Neil van Schalkwyk, a partner at Masincedane Sport, said he developed a plastic version after spotting the original horns being blown at games.

Following the welter of complaints, Van Schalkwyk’s company has come up with a quieter version.

“We have modified the mouthpiece, there is now a new vuvuzela which will blow noise that is 20 decibels less than the old one,” Van Schalkwyk told The Star newspaper.

“We hope to sell these at park-and-ride areas and public viewing areas,” added Van Schalkwyk, whose company owns the vuvuzela trademark.

The company says it has sold 1.5 million vuvuzelas in Europe since October, and expects the tournament will generate sales of up to US$2.6-million.